Tin foil. What can it mean?

My neighbour next-door-but-one is a bit of a recluse. She sleeps all day and surfs the net all night. She has taken various trips abroad to the US to meet people in person that she has chatted to on the net. Last time, she ended up in Las Vegas and in hospital. She was held captive by some nut for a day and beaten up really badly. She didn't press charges. She came back looking awful. Next, she went around the Caribbean for another eight months crewing on a small ship. How do I know this? Because my nosey neighbours nextdoor told me.

She has got dyed blonde hair and a cat which she loves likes a person. I know that she has a really sad family background and was in care for most of her teens. I used to always stop and chat but I've noticed that she really hides away now. The only person that seems to visit is her brother. Lately, she has covered all her windows from the inside with kitchen foil. A bit weird if you ask me. We were talking about it the other night. My other half reckons it is because she sleeps all day and has done it to block out the light. My theory was that she was growing weed. No one seems to know. I bumped into her really briefly the other day and forgot to ask!! Odd.